Early Detection of Cercospora Species in Soybean Plants: Immunologic and Molecular Methods.

LATORRE RAPELLA; LURA CRISTINA; MARCIPAR IVÁN

American Journal of Plant Sciences

Scientific Research

Año: 2015 vol. 6 p. 2939 - 2948

Late-cycle diseases (LCD) cause a significant deterioration in quality and reduce yields in soybeancrops. In Argentina, in particular, leaf blight and purple seed stain, caused by the agent Cercosporakikuchii, and frog eye spot, caused by C. sojina, are the prevailing sources of diseases. The early,rapid and accurate detection of these phytopathogens becomes essential, and would contribute topreserving both the environment and the health of humans and animals by preventing the wastefulor improper use of chemicals such as pesticides. In order to detect Cercospora species in soybeanplants at an early stage, immunochemical and molecular techniques were developed in thiswork. Strains from the NITE Biological Resource Center collection (Japan): Cercospora kikuchiiNBRC 6711 and Cercospora sojina NBRC 6715 and regional isolates of C. kikuchii were used. Todevelop Dot-Blot and PCR techniques, experiments with plants undergoing different treatmentswere carried out: those experimentally inoculated with these fungi, those treated with sterile waterand healthy plants as well. Both techniques allowed the detection, at early stages, of Cercosporaspecies involved in two of the most frequent LCD in the country, when the cercosporin concentrationproduced by the fungus was higher than 3.93 ± 0.39 nmol∙cyl−1 ±SD. The sensitivity betweenboth techniques was very different. While Dot-Blot allowed the detection of the disease 4days after inoculation, PCR detected it after 4 hours, even without visible symptoms of the disease.